1. Technical Field
The present disclosure relates to a rectifying device, in particular, to a rectifying module, an electric apparatus thereof and a rectifying method thereof for charging using alternating current signal.
2. Description of Related Art
With the continuously growing popularity of battery-powered consumer electronic devices such as portable multimedia players, smart phones, and tablets, chargers with bundles of cables are commonly seen almost everywhere in one's household. Although, wired chargers are operable for providing stable signal, however the rectifying circuit thereof in general requires the use of diodes with high breakdown voltage and diodes with high breakdown voltage are costly. Moreover, there are disadvantages with using wired battery chargers such as creating wiring mess in the living space, placing distance limitation between the electronic device and the charger, cost consideration on the associated cable or wires, as well as creating inconvenience to the user. As a result, demand for wireless transmission gradually increases.
Moreover, following the rapid development of wireless technology, there is a growing trend toward the use of wireless charging. It is inevitable trend for the electronic device to adopt wireless power transmission to increase the flexibility, functionality and convenience of the electronic device as wireless power transmission technology can overcome the long-term issue of wired chargers having to charge devices through cables.
Exiting wireless charging technologies include capacitor coupling, microwave, electromagnetic coupling, electromagnetic induction, electromagnetic resonance, and the like, wherein electromagnetic induction and LC resonance circuit have been widely used in wireless power transmission. The main component for a wireless charging system using electromagnetic induction is the radio frequency (RF) rectifier, therefore the power conversion efficiency and input power of the RF rectifier has significant impacts on the chagrining efficiency of the wireless charging system using electromagnetic induction
In addition, silicon-based Schottky diodes are general used as the rectifying component for either conventional wired chargers or wireless chargers. However, excessive RF input power could operatively cause resonance in a Schottky diode generated in response to the input current and input voltage, which might cause the junction between metal and semiconductor to breakdown which could damage the Schottky diode. Hence, the input power for the conventional rectifier is in practice configured to be lower than 30 dB. Additionally, the conversion efficiencies for conventional rectifiers are generally low.
In order for the rectifier to operate with higher input power, industries have come up with Gallium-nitride (GaN)-based Schottky diodes for increasing the breakdown voltage of the rectifier. In comparison to the silicon-based Schottky diodes having breakdown voltage of 15V, Gallium-nitride (GaN)-based Schottky diodes has higher breakdown voltage such as 90V. However, Gallium-nitride (GaN)-based Schottky diodes are costly, thus under cost consideration, Gallium-nitride (GaN)-based Schottky diodes are not suited for silicon-based semiconductor manufacturing processes.